Vulnerabilities > CVE-2018-4844 - Improper Privilege Management vulnerability in Siemens Simatic Wincc OA UI
Summary
A vulnerability has been identified in SIMATIC WinCC OA UI for Android (All versions < V3.15.10), SIMATIC WinCC OA UI for iOS (All versions < V3.15.10). Insufficient limitation of CONTROL script capabilities could allow read and write access from one HMI project cache folder to other HMI project cache folders within the app's sandbox on the same mobile device. This includes HMI project cache folders of other configured WinCC OA servers. The security vulnerability could be exploited by an attacker who tricks an app user to connect to an attacker-controlled WinCC OA server. Successful exploitation requires user interaction and read/write access to the app's folder on a mobile device. The vulnerability could allow reading data from and writing data to the app's folder. At the time of advisory publication no public exploitation of this security vulnerability was known. Siemens confirms the security vulnerability and provides mitigations to resolve the security issue.
Vulnerable Configurations
Common Weakness Enumeration (CWE)
Common Attack Pattern Enumeration and Classification (CAPEC)
- Restful Privilege Elevation Rest uses standard HTTP (Get, Put, Delete) style permissions methods, but these are not necessarily correlated generally with back end programs. Strict interpretation of HTTP get methods means that these HTTP Get services should not be used to delete information on the server, but there is no access control mechanism to back up this logic. This means that unless the services are properly ACL'd and the application's service implementation are following these guidelines then an HTTP request can easily execute a delete or update on the server side. The attacker identifies a HTTP Get URL such as http://victimsite/updateOrder, which calls out to a program to update orders on a database or other resource. The URL is not idempotent so the request can be submitted multiple times by the attacker, additionally, the attacker may be able to exploit the URL published as a Get method that actually performs updates (instead of merely retrieving data). This may result in malicious or inadvertent altering of data on the server.